From 26f53cd385fab9dabec50b4a7be07041db929417 Mon Sep 17 00:00:00 2001 From: Tom Tromey Date: Thu, 18 Feb 2021 11:23:33 -0700 Subject: [PATCH] Introduce expression::evaluate This introduces a new method, expression::evaluate, and changes the top-level expression-evaluation functions to use it. Stack temporary handling is moved into this new method, which makes sense because that handling was only done when "*pos == 0". This patch avoids some temporary regressions related to stack temporary in the larger expression rewrite series. I've pulled it out separately because it seems like a reasonable change in its own right, and because it's better to avoid making that series even longer. Regression tested on x86-64 Fedora 32. gdb/ChangeLog 2021-02-18 Tom Tromey * expression.h (struct expression) : Declare method. * eval.c (evaluate_subexp): Simplify. (expression::evaluate): New method. (evaluate_expression, evaluate_type): Use expression::evaluate. --- gdb/ChangeLog | 7 +++++++ gdb/eval.c | 47 +++++++++++++++++++++++++---------------------- gdb/expression.h | 5 +++++ 3 files changed, 37 insertions(+), 22 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 030eb9f5983..0349d44851e 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,10 @@ +2021-02-18 Tom Tromey + + * expression.h (struct expression) : Declare method. + * eval.c (evaluate_subexp): Simplify. + (expression::evaluate): New method. + (evaluate_expression, evaluate_type): Use expression::evaluate. + 2021-02-17 Kevin Buettner * ada-lang.c (ada_fold_name): Check for non-empty string prior diff --git a/gdb/eval.c b/gdb/eval.c index e63511b7005..8256fdea148 100644 --- a/gdb/eval.c +++ b/gdb/eval.c @@ -61,22 +61,8 @@ struct value * evaluate_subexp (struct type *expect_type, struct expression *exp, int *pos, enum noside noside) { - struct value *retval; - - gdb::optional stack_temporaries; - if (*pos == 0 && target_has_execution () - && exp->language_defn->la_language == language_cplus - && !thread_stack_temporaries_enabled_p (inferior_thread ())) - stack_temporaries.emplace (inferior_thread ()); - - retval = (*exp->language_defn->expression_ops ()->evaluate_exp) - (expect_type, exp, pos, noside); - - if (stack_temporaries.has_value () - && value_in_thread_stack_temporaries (retval, inferior_thread ())) - retval = value_non_lval (retval); - - return retval; + return ((*exp->language_defn->expression_ops ()->evaluate_exp) + (expect_type, exp, pos, noside)); } /* Parse the string EXP as a C expression, evaluate it, @@ -121,14 +107,33 @@ parse_to_comma_and_eval (const char **expp) } +/* See expression.h. */ + +struct value * +expression::evaluate (struct type *expect_type, enum noside noside) +{ + gdb::optional stack_temporaries; + if (target_has_execution () + && language_defn->la_language == language_cplus + && !thread_stack_temporaries_enabled_p (inferior_thread ())) + stack_temporaries.emplace (inferior_thread ()); + + int pos = 0; + struct value *retval = evaluate_subexp (expect_type, this, &pos, noside); + + if (stack_temporaries.has_value () + && value_in_thread_stack_temporaries (retval, inferior_thread ())) + retval = value_non_lval (retval); + + return retval; +} + /* See value.h. */ struct value * evaluate_expression (struct expression *exp, struct type *expect_type) { - int pc = 0; - - return evaluate_subexp (expect_type, exp, &pc, EVAL_NORMAL); + return exp->evaluate (expect_type, EVAL_NORMAL); } /* Evaluate an expression, avoiding all memory references @@ -137,9 +142,7 @@ evaluate_expression (struct expression *exp, struct type *expect_type) struct value * evaluate_type (struct expression *exp) { - int pc = 0; - - return evaluate_subexp (nullptr, exp, &pc, EVAL_AVOID_SIDE_EFFECTS); + return exp->evaluate (nullptr, EVAL_AVOID_SIDE_EFFECTS); } /* Evaluate a subexpression, avoiding all memory references and diff --git a/gdb/expression.h b/gdb/expression.h index e70169e9b3e..397a0af9aba 100644 --- a/gdb/expression.h +++ b/gdb/expression.h @@ -120,6 +120,11 @@ struct expression return elts[0].opcode; } + /* Evaluate the expression. EXPECT_TYPE is the context type of the + expression; normally this should be nullptr. NOSIDE controls how + evaluation is performed. */ + struct value *evaluate (struct type *expect_type, enum noside noside); + /* Language it was entered in. */ const struct language_defn *language_defn; /* Architecture it was parsed in. */ -- 2.30.2